in (或 out of) condition

in a fit (or unfit) physical state

健康狀況良好（或不佳）

in no condition to do something

certainly not fit or well enough to do something

（健康狀況，身體狀況）不適宜做某事

you’re in no condition to tackle the stairs.

你的身體不適宜爬樓梯。

on condition that

with the stipulation that

如果…就；只有在…條件下

I got three years' probation, on condition that I stay at the hostel for a year.

我得到三年試用期，條件是我必須在招待所呆滿一年。